Lorraine, your reply is a useful but small step forward.
However you didnt give any rivet details.
now you need to go to Ebay UK and type in model engineering rivets.
Thats the size ie mostly 1/16in dia you should be using with the
round head on the copper sheet. tho they will be hard and need
annealing if your riveting to ali. Copper harder than ali? get it?
use stainless steel as a backing, a much better option…
This needs to be at least 1.5 mm thick. Less is not thick enough.
this can be counter sunk 120deg by 3mm wide so the rivet is flush
with the inside.
Also google, for aircraft riveting specifications. as your using
industrial joining techniques in jewellery you need to know what
size rivets are used on what thickness sheet. Know how thats been
around since the 1930’s.
Next you need to think of the tension load on the copper sheet
pulling on the rivet in shear. The no of rivets you need have to give
more strength than the load stretching the copper sheet when bent
around the cuff mandrel. Just simple engineering really. its all been
done before. If you cant hide a joining/ assembly technique, turn it
into part of the design.
As Ive said before do your research and run lots of trials your
learn so much that way. Once youve got the materials right and the
technique right, youll be making them by the dozen in all the
different sizes . Then have lots of sales.
do sign and date them as well with hand stamps.
Youll owe me one for all this inside know how on profit making!!.